If your National Insurance record has gaps, your State Pension could be smaller than you expect. The good news is that you can often fill those gaps by paying voluntary contributions, and for many people it is one of the best value deals in personal finance.
But it is not right for everyone. Some people pay and see no increase at all. Here is how to check whether topping up is worth it for you, what it costs, and the deadlines to watch.
Quick answer: A full year of voluntary Class 3 National Insurance costs £956.80 from April 2026 (£18.40 a week). It could add about £358 a year to your State Pension for life, so you would get your money back in under three years. You can usually fill gaps from the last 6 tax years. Always check your State Pension forecast first, because paying does not always increase your pension.
In this guide
- Why you might have gaps
- How much it costs in 2026/27
- How much it could add to your State Pension
- When it is not worth paying
- Free alternatives: National Insurance credits
- Deadlines
- Changes for people living abroad
- How to pay, step by step
Why do people have gaps in their National Insurance record?
You build up your State Pension through “qualifying years” on your National Insurance record. You need 35 qualifying years for the full new State Pension, and at least 10 to get anything at all.
A year might not count if you:
- were employed but earned below the threshold for National Insurance
- were not working and did not claim benefits
- were self-employed with low profits
- lived or worked abroad
- retired early and are not yet at State Pension age
- only got National Insurance credits for part of the year
How much do voluntary contributions cost?
There are two types:
- Class 3: £18.40 a week from April 2026. This is the type most people pay. A full year costs £956.80.
- Class 2: £3.65 a week from April 2026. This much cheaper option is only for some self-employed people.
You do not always need to buy a whole year. If you already have some contributions or credits in a tax year, your National Insurance record will show the cost of just the shortfall.
One quirk on pricing: for Class 3 from the previous two tax years, you pay the original rate for that year. For older years, you pay the current year’s rate.
How much could it add to your State Pension?
The full new State Pension is £241.30 a week from April 2026. Each extra qualifying year adds about 1/35 of that, which works out at roughly:
- £6.89 a week
- about £358 a year
- for the rest of your life, and rising each year with the State Pension
So £956.80 spent now could pay for itself in under three years of retirement. Over a 20-year retirement, one year bought could be worth more than £7,000 before tax. Bear in mind the State Pension is taxable income, so if you pay income tax, you will keep a little less of it.
When paying is not worth it
This is where people get caught out. Voluntary contributions do not always increase your State Pension. It may not be worth paying if:
- You will reach the full amount anyway. If you still have enough working years left before State Pension age, you may fill the gaps naturally.
- You were contracted out. If you had a National Insurance record before April 2016 and were contracted out of the old additional State Pension, the rules are different. Some people need more than 35 years, and some are already at their maximum.
- You are already forecast the full amount. You cannot pay to go above it.
- You could get credits for free instead (see below).
The safest step is to check your forecast before paying. The Check your State Pension forecast service shows your gaps, how much each one would cost, and whether filling it would increase your pension. If you are unsure, contact the Future Pension Centre (if you are under State Pension age) or the Pension Service (if you have reached it) before you pay anything.
Check for free credits first
Before you pay, see whether you should have received National Insurance credits for that year. Credits fill gaps for free. You may get them if you were, for example:
- claiming Child Benefit for a child under 12
- a carer, getting Carer’s Allowance or caring for someone for at least 20 hours a week
- claiming certain benefits because you were ill, disabled or looking for work
- a grandparent or other family member looking after a child under 12 while the parent worked
That last one is often missed. Read our guide to how grandparents can get National Insurance credits for childcare. It can fill gaps back to April 2011 without paying a penny.
Deadlines: you usually have 6 years
You can normally only pay for gaps in the last 6 tax years. The deadline is 5 April each year.
- Gaps in the 2019 to 2020 tax year must be paid by 5 April 2026.
- Gaps in the 2020 to 2021 tax year must be paid by 5 April 2027.
- Gaps in the 2025 to 2026 tax year can be paid until 5 April 2032.
The special extension that let people fill gaps back to 2006 ended on 5 April 2025, so the 6-year rule now applies again. If you have a gap from 2019 to 2020, now is the time to act.
Changes from April 2026 if you live abroad
Many British people who retire abroad pay voluntary contributions to keep their State Pension growing. The rules tighten from 6 April 2026:
- You can no longer pay the cheap Class 2 contributions for time spent abroad.
- To pay Class 3 for time abroad, you will need to have lived in the UK for 10 years in a row, or have paid 10 years of contributions in total. Previously it was 3 years.
If you applied before 6 April 2026, the older rules may still apply to you. If you live abroad and are close to State Pension age, contact the International Pension Centre for advice.
How to pay, step by step
- Check your State Pension forecast on GOV.UK or in the HMRC app. Note any years marked as not full.
- Check whether you can get credits for those years instead.
- Confirm paying would help. The forecast service shows whether each gap would increase your pension. If you are unsure, call the Future Pension Centre.
- Pay. The simplest way is online through the forecast service, where your record usually updates within 5 working days. You can also pay by bank transfer, direct debit, at your bank, or by cheque, which can take up to 8 weeks to show.
- Check your record afterwards to confirm the year now shows as full.
Be wary of anyone who contacts you offering to fill your National Insurance gaps for a fee. You can do it yourself, for free, on GOV.UK. Our guide to avoiding scams in retirement explains the warning signs.
Frequently asked questions
Can I pay voluntary contributions after I reach State Pension age?
You can still pay for gaps in years before you reached State Pension age, within the 6-year limit. Contact the Pension Service first, as your pension will need to be recalculated.
Will paying increase my partner’s pension?
No. The new State Pension is based on your own National Insurance record only.
Should I pay for the oldest gap first?
Usually, yes, if it is close to its deadline. Once the deadline passes, you lose the chance to fill it.
Is it better than putting the money in a private pension?
For many people, a year of State Pension is very good value because it is guaranteed, rises each year and lasts for life. But everyone’s situation is different. Our guide to getting financial advice for retirement explains when it is worth talking to an expert.
Final thoughts
Topping up your State Pension can be one of the best returns available, but only if it actually increases your pension. Check your forecast, look for free credits first, and keep an eye on the 5 April deadline every year.
To understand the rest of your State Pension, read our guides to State Pension eligibility and how to claim your State Pension. If you are thinking of stopping work early, see the pros and cons of retiring early in the UK.
